Trench duct connecting device with vertical adjustment means

ABSTRACT

A device for installing trenchduct, the device having a bottom and three upstanding sides, one side securing the device to the trench by being welded thereto, the other two sides being used alternatively for coupling one trench to another and the bottom being used either to secure the trench to a cellular floor by being welded thereto or alternatively supporting a leveling lug when the trench is used over a concrete floor.

United States Patent Frederick W. I-Iudnall Vienna, W. Va. 849,991

Aug. 14, I969 May I I, 197 I Textron Inc. Providence,-R.l.

inventor Appl. No. Filed Patented Assignee TRENCH DUCT CONNECTING DEVICEWITH VERTICAL ADJUSTMENT MEANS 4 Chins, 3 Drawing Fig.

usml 52/220, 52/122, 52/714, 285/406 Int. Cl E041 1710:;

Field ofSearch 52/220,

References Cited UNITED STATES PATENTS 1,782,779 11/1930 Fullman 52/2212,001,574 5/1935 Jacobson 52/122 2,020,502 1 H1935 Goddard 52/2382,812,654 11/1957 Hoseason 220/3.4X 3,061,663 10/ 1962 Reiland 52/221X3,331,916 7/1967 George etal. 174/101X 3,435,568 4/1969 Hoseason et a152/221 Primary Examiner-Alfred C. Perharn Attorney-Frederick .I OlssonABSTRACT: A device for installing trenchduct, the device having a bottomand three upstanding sides, one side securing the device to the trenchby being welded thereto, the other two sides being used altemativeiy forcoupling one trench to another and the bottom being used either tosecure the trench to a cellular floor by being welded thereto or.alternatively supporting a leveling lug when the. trench is used over aconcrete floor.

TRENCII DUCT CONNECTING DEVICE WITH VERTICAL ADJUSTMENT MEANS Thisinvention, in general, relates to trenchduct for electrical underfloordistribution systems.

More specifically, the invention relates to a device having a specialutility in connection with the installing of trenchduct on cellularfloors, on concrete floors or on blended floors, the device beinginterchangeably useable for such type of floors.

The principal object of the invention is to provide a device of the kindin question characterized by a single unitary structure having a designso that a desired number of identical devices can be secured atdifferent places on a trenchduct for respectively performing thefunction of joining adjacent trenches together, the function of securingthe trench down against the top of cells when the same is used over acellular floor and the function of leveling the trench when used overconcrete floor.

The invention has special advantage to the producer by savings inmanufacturing costs and advantage to the installer or contractor bysavings in installation and repair costs.

The manner in which the invention is constructed and the variousadvantages thereof will be described and commented on below inconnection with the following drawings wherein:

FIG. I is a perspective view of a typical trenchduct incorporating theinvention;

FIG. 2 is a perspective view of the device of the invention;

FIG. 3 is a fragmentary view illustrating one of the connective devicesof FIG. 1 as used for coupling adjacent trenches.

In FIG. 1 the trench 1 has an elongated, horizontally extending channel2. The reversible Z-shaped tile trim pieces 3 and 4 are mounted on thechannel by means providing for adjustment in a vertical direction. Thecovers 5, 6 and 7 are supported on the tile trim and extend across thechannel. The channel is mounted directly on the cells 10 of the cellularfloor 11. The foregoing structure is conventional.

Along the wall 12 of the trench are a plurality of connecting devices13, 14 and 15. The opposite wall 16 has similar devices one of which isindicated at 17.

The connecting devices are all identical in structure, the details ofwhich are shown in FIG. 2 for the connecting device 13.

The device is formed preferably from mild sheet steel and is either 12of 14 gauge.

The bottom of the device is comprised of a pair of the flat,rectangular-shaped, spaced-apart mounting plates 21 and 22. The plate 21has an inner edge 23 and an outer edge 24. The plate 22 has an inneredge and an outer edge 26. The inner edges 23 and 25 face one another.The plate 21 has a side edge and the plate 22 has a side edge 31. Theplates 21 and 22 are identical in shape and size.

A rectangular-shaped bridge 32 is connected to the inner edges 23 and 24and extends across the space between the plates. The top 33 of thebridge is spaced above the plates 21 and 22. The top has an aperture 34which is adapted to hold a Riv-nut or a nut and bolt retainer forpurposes of holding a leveling lug as will be explained later.

Extending up from the outer edge 24 is a coupling flange 35 andextending up from the outer edge 26 is a coupling flange 36. Thecoupling flange 35 has apertures while the coupling flange 36 hasapertures 41. The coupling flanges 35 and 36 and the apertures 40 and 41are identical in shape and in size. Both of the flanges 40 and 41 arenormal to the plates 21 and 22.

Extending upwardly from the outside edge 30 is a welding flange 42 andconnected to and extending up from the outside edge 31 is a weldingflange 43 which preferably is the same size and shape as flange 42. Thetop 33 of the bridge 32 also has a welding flange 44. The flanges 42 and43 are normal to theplates 21 and 22 and the flange 44 is normal to top33.

In cases where the connector is made from 14 gauge metal I providebosses at the intersection of the welding flanges and mounting plates,for example, the bosses 45 and 46. With 12 gauge I found the boxes to beunnecessary. The purposes of the boss is to give strength and rigidityand to maintain the normal relationship between the upstanding weldingflanges and the mounting plates.

The foregoing described structure provides for a connecting device whichis universally applicable to a trench to perform any of the requiredfunctions either on cellular or on concrete floors.

The welding flange 42, 43 and 44 are used for securing the device to thesides of the trench.

Preferably this is done during manufacture by spot welding in severalpositions on each flange. For example in FIG. 3 the flanges 42, 43 and44 of the connecting device 13 are spot welded to the side 12 as by thewelds indicated at 47.

For rigidly connecting the trench to the cellular floor the mountingplates are 21 and 22 welded to the top of the cell. For example in FIG.3 it will be observed that the plates 21 and 22 are welded in by thefillet welds 50 and 51. The same fillets are shown in FIG. 1.

In the embodiment shown in FIG. 1 the connecting devices 14 and 15 onthe side 12 of the trench and their counterparts on the opposite side 16of the trench are all welded to the cells in the same manner asdescribed for the connecting device 13. This insures that the trench isfirmly down in engagement with the top which is required for approvedinstallations particularly since in many cases the trench bottom hasaccess holes in communication with a cell which is used as a conductoror cable raceway.

lncidently, the following is to be observed in welding up the connectingdevices to the trench it is important that the bottom mounting plates beflush or aligned with the bottom of the trench in order that the devicewill properly seat the trench on the cells of a cellular floor.

For coupling adjacent trenches together, pairs of connecting devices arepositioned on the ends of the trenches so that when the trenches areplaced in position corresponding coupling flanges about one another andare bolted together. For example in HG. 3 the trench 1 has theconnecting device 13 and the trench 52 has connecting device 53. Thecoupling flange 40 of the device 13 abuts the coupling flange 54 of thedevice 52. The two flanges are held together as by the nut-bolt 55. Theopposite side of the trench has an identical arrangement.

The trench with the connecting devices installed as described above issuitable for use over concrete without change except for the addition ofleveling lugs. In this connection it is to be noted in FIG. 2 that Ihave shown the aperture 34 of the device 13 without a Riv-nut or anut-bolt retainer while in FIG. 1 l have shown the device 13 (and thedevices 14 and 15) with Riv-nuts installed in the apertures of thebridges and conditioned to receive leveling lugs of conventional form.

The trench may be supplied with the Riv-nuts or nut-bolt retainersalready installed or alternatively the trench can be supplied withoutany Riv-nut or equivalent device and in such instances on-the-jobinstallation of nut-bolt retainer or other equivalent means iscontemplated The fact that the trenches are applicable either forcellular floors or for concrete floors simply by the addition of aleveling lug'is of special advantage in blended floor situations. Fromthe manufacturer's standpoint the structure eliminates any necessity forsupplying trenches which have special brackets in order to make thetrench compatible with the type of floor. From the contractorsstandpoint the structure eliminates any likelihood that the contractorwill have to make special provisions for mounting the trench in theevent during.

strength. This if of particular importance where the trench is.

used over concrete floors inasmuch as after the trench is leveled it islikely to receive heavy loads not only from workmen walking on thetrench but from wheelbarrows, cement carts and the like being pushedover the same. It often happens that with conventional arrangements fortrench leveling, the loads imposed are severe enough to cause collapseand as a consequence extensive repairs have to be made by thecontractor. The load-bearing qualities of the connectors of theinvention is more than double the load-bearing qualities of conventionalleveling means.

The combining of the coupling function, the leveling function and thewelding function into a single unitary piece universally useable pieceis of special advantage to the manufacture in that by a single operationof welding a device on the side of a trench there is provided a singlemeans capable of performing multiple functions. The conventional mannerof providing mechanism for coupling, leveling and welding contemplatesat least three separate bracket means all of which must be welded to thetrench in three separate operations.

lclaim:

l. A unitary connecting device for use in installing trenchduct oncellular, concrete and blended floors, the device being made from metaland being formed so as to have:

a pair of flat, rectangular-shaped, spaced-apart mounting plates to bedisposed on the top of cells of cellular floor and welded thereto oralternatively to be disposed over the surface of a concrete floor andleveled with respect thereto, each plate having an inner edge, an outeredge and a side edge extending therebetween with the inner edges facingone another;

a pair of welding flanges respectively connected to said side edges andextending normally upwardly from said mounting plates, the flanges beingfor use in welding the device to the side of a trench;

a bridge connected to said inner edges and extending over the spacebetween the plates with the top of the bridge being spaced above saidmounting plates, the top having an aperture for use in retaining a nutto accept a leveling screw for use when the device is over a concretefloor; and

a pair of coupling flanges respectively connected to said outer edgesand extending normally, upwardly, from said mounting plates, eachcoupling flange having aperture means for accepting coupling bolts whenthe device is used for coupling adjacent trenches together;

2. A construction in accordance with claim 1 further including at leastone boss at the intersection of each mounting plate and its weldingflange.

3. A construction in accordance with claim 1 further including a weldingflange on said bridge and extending upwardly in the same direction asfirst said welding flanges.

4. A construction in accordance with claim 1 further including a nut insaid aperture.

1. A unitary connecting device for use in installing trenchduct oncellular, concrete and blended floors, the device being made from metaland being formed so as to have: a pair of flat, rectangular-shaped,spaced-apart mounting plates to be disposed on the top of cells ofcellular floor and welded thereto or alternatively to be disposed overthe surface of a concrete floor and leveled with respect thereto, eachplate having an inner edge, an outer edge and a side edge extendingtherebetween with the inner edges facing one another; a pair of weldingflanges respectively connected to said side edges and extending normallyupwardly from said mounting plates, the flanges being for use in weldingthe device to the side of a trench; a bridge connected to said inneredges and extending over the space between the plates with the top ofthe bridge being spaced above said mounting plates, the top having anaperture for use in retaining a nut to accept a leveling screw for usewhen the device is over a concrete floor; and a pair of coupling flangesrespectively connected to said outer edges and extending normally,upwardly, from said mounting plates, each coupling flange havingaperture means for accepting coupling bolts when the device is used forcoupling adjacent trenches together;
 2. A construction in accordancewith claim 1 further including at least one boss at the intersection ofeach mounting plate and its welding flange.
 3. A construction inaccordance with claim 1 further including a welding flange on saidbridge and extending upwardly in the same direction as first saidwelding flanges.
 4. A construction in accordance with claim 1 furtherincluding a nut in said aperture.